Atomic scalar magnetometers, or scalar magnetometers, measure total magnetic field, and are substantially insensitive to orientation and vibration. Scalar magnetometers are widely used in geophysical and object search surveys where the magnetometers may be in motion. Modern magnetometer cells are on the order of one hundred cubic centimeters in volume. A corresponding magnetometer system consumes watts of power because of a required power level of a pump laser to operate the system. The pump laser spin polarizes atoms in the cell to detect the magnitude of incident magnetic fields.
Smaller atomic magnetometer cells, which can include smaller optical cavities, are desirable because not only do they facilitate smaller magnetometer systems, but also because the systems consume significantly less power because the pump laser can operate at much lower power levels. As the volume of an atomic magnetometer cell, and e.g. cavity, diminishes, the optical path length likewise diminishes, thereby reducing the magnitude of the magnetometer signal and thus magnetometer sensitivity. Therefore, there is a need for a small cavity-based atomic magnetometer system whose sensitivity is not so diminished.